Leakage and noise cancelling for double balanced duplexers

ABSTRACT

Systems and method are described for improving electrical isolation between a transmission signal and receiver circuitry of a transceiver communicating over one or more wireless networks via one or more shared antennas. The transceiver may include isolation circuitry to facilitate isolation of the transmission signal from the receiver circuitry. However, a leakage current of the transmission signal and noise signals may appear at the receiver circuitry. Presence of the leakage current or the noise signals in the receiver circuitry may cause interference with the reception signal. As such, the isolation circuitry may benefit from additional isolation between the transmission signal and the receiver circuitry to reduce an effect of the leakage current and the noise signals on the reception signal.

BACKGROUND

The present disclosure relates generally to wireless communicationsystems and, more specifically, to isolating receivers from transmissionsignals in wireless communication devices.

This section is intended to introduce the reader to various aspects ofart that may be related to various aspects of the present disclosure,which are described and/or claimed below. This discussion is believed tobe helpful in providing the reader with background information tofacilitate a better understanding of the various aspects of the presentdisclosure. Accordingly, it should be understood that these statementsare to be read in this light, and not as admissions of prior art.

Electronic devices are being used more and more every day to transferdata between users, to control smart home devices, stream movies andshows, and so on. As the amount of data being communicated usingelectronic devices is increasing, maintaining integrity of thecommunicated data becomes more and more important. For example, in anelectronic device, a transmitter and a receiver may be coupled to one ormore antennas to enable the electronic device to transmit and receivewireless signals. To increase an amount of data able to be sent andreceived and decrease a time between sending and receiving the data, theelectronic device may enable full duplex operations (e.g., sending datawhile receiving data) via frequency division duplexing (FDD). That is,transmission signals may be sent via the one or more antennas over afirst frequency range while received signals may be received via the oneor more antennas over a second frequency range different than the first.To enable these FDD-full duplex operations, the electronic device mayinclude isolation circuitry that isolate transmission signals from thereceiver and isolate the received signals from the transmitter.

The transmitter includes a power amplifier that amplifies a transmissionsignal so that the transmission signal may be provided to the one ormore antennas with sufficient transmission power. However, the amplifiermay introduce noise to the transmission signals (e.g., in the receivefrequency band) that may result in interference and reduced datareliability at the receiver of the electronic device.

Moreover, certain electronic devices may use electrical components(e.g., baluns) that may isolate the transmitter from received signals,and the receiver from transmission signals. However, the electricalcomponents may provide less than ideal isolation between thetransmission signal and the receiver due to non-ideal characteristics ofreal-world electrical components. This less than ideal isolation maylead to leakage of the transmission signal to the receiver, which maycause interference at the receiver.

SUMMARY

A summary of certain embodiments disclosed herein is set forth below. Itshould be understood that these aspects are presented merely to providethe reader with a brief summary of these certain embodiments and thatthese aspects are not intended to limit the scope of this disclosure.Indeed, this disclosure may encompass a variety of aspects that may notbe set forth below.

In some embodiments, the isolation circuitry may extend one or moreauxiliary signal paths between the transmission circuitry and thereceiver circuitry to reduce an effect of the leakage current and/or thenoise signals in reception signal. Such auxiliary signal paths mayprovide one or more feedback signals from the transmission circuitry tothe receiver circuitry to cancel the leakage current and/or the noisesignals. The one or more feedback signal may include an adjusted portionof the transmission signal. The auxiliary signal paths may each includephase adjustment circuitry. For example, a first auxiliary signal pathmay provide the first feedback signal 180 degrees out of phase comparedto the transmission signal to cancel the leakage current. In someembodiments, the auxiliary signal paths may also include gain adjustmentcircuitry. The gain adjustment circuitry may adjust a current or anamplitude of the first feedback signal to reduce or cancel the leakagecurrent.

In different embodiments, the first auxiliary signal path may beconnected to the transmitter circuitry before the PA (e.g., an inputnode of the PA) or after the PA (e.g., an output node of the PA). In thefirst embodiment, the first auxiliary signal path is connected to thetransmitter circuitry before the PA. The first feedback signal mayprovide an adjusted portion of the transmission signal for cancellingthe leakage current at the receiver circuitry. The first auxiliarysignal path may include phase adjustment circuitry and/or gainadjustment circuitry to provide the adjusted portion of the transmissionsignal for cancelling the leakage current.

In a second embodiment, the first auxiliary signal path is connected tothe transmitter circuitry after the PA. The first feedback signal mayprovide the adjusted portion of the transmission signal with the noisesignals (e.g., generated by the PA) for cancelling the leakage currentat the receiver circuitry. The first auxiliary signal path may includephase adjustment circuitry and/or gain adjustment circuitry to providethe adjusted portion of the transmission signal for cancelling theleakage current. Moreover, in the second embodiment, the first auxiliarysignal path may include a bandpass filter to prevent the noise signalsfrom distorting the first feedback signal. That is, the bandpass filtermay allow a portion of the first feedback signal that is within thetransmission frequency band to cancel the leakage current and prevent aportion of the first feedback signal that is outside the transmissionfrequency band from the receiver circuitry.

In a third embodiment, the isolation circuitry may extend a secondauxiliary signal path between the transmission circuitry and thereceiver circuitry to reduce or cancel the noise signals. The secondauxiliary signal path may provide a second feedback signal from thetransmission circuitry to the receiver circuitry to cancel the noisesignals of the transmission signal within the reception frequency band.The second feedback signal may include a different adjusted portion ofthe transmission signal to cancel the noise signals at the receivercircuitry. The second auxiliary signal path may include phase adjustmentcircuitry and/or gain adjustment circuitry to provide the adjustedportion of the transmission signal for cancelling the noise signals atthe receiver circuitry.

In one embodiment, a radio frequency transceiver circuitry may include afirst balun and a second balun. The first balun and the second balun maybe electrically coupled to one or more antennas. The radio frequencytransceiver circuitry may also include transmit circuitry electricallycoupled to the first balun. The transmit circuitry may send atransmission signal via the one or more antennas. The radio frequencytransceiver circuitry may include receiver circuitry. The receivercircuitry may electrically couple to the second balun. Moreover, thereceiver circuitry may receive a receive signal using the one or moreantennas. The radio frequency transceiver circuitry may also includephase adjustment circuitry. The phase adjustment circuitry mayelectrically couple between the transmit circuitry and the second balun.The phase adjustment circuitry may adjust a phase of a feedback signal.Moreover, the phase adjustment circuitry may provide the feedback signalfrom the transmit circuitry to the second balun to compensate for aleakage or noise signal generated by the transmit circuitry when sendingthe transmission signal via the one or more antennas.

In another embodiment, an electronic device may include one or moreantennas. The electronic device may also include transmission circuitryto send a transmission signal to the one or more antennas. The receivercircuitry configured to receive a reception signal from the one or moreantennas. The electronic device may also include isolation circuitry toprovide electrical isolation between the transmission signal and thereceiver circuitry. Moreover, the isolation circuitry may provideelectrical isolation between the reception signal and the transmissioncircuitry. The electronic device may also include a feedback pathbetween the transmission circuitry and the receiver circuitry. Thefeedback path may provide a feedback signal from the transmissioncircuitry to the receiver circuitry. The electronic device may alsoinclude a phase adjustment circuitry disposed on the feedback path. Thephase adjustment circuitry may adjust a phase of the feedback signal tocompensate for a leakage or noise signal generated by the transmissioncircuitry when sending the transmission signal to the one or moreantennas.

In yet another embodiment, an electronic device may include antennameans, means for transmitting a transmission signal via the antennameans, means for receiving a receive signal via the antenna means, andmeans for isolating the receiving means from the transmission signal.The isolating means may include means for providing a feedback signalfrom the transmitting means to the receiving means. Moreover, theisolating means may include means for adjusting a phase of the feedbacksignal to compensate for a leakage or noise signal generated by thetransmitting means when transmitting a transmission signal via theantenna means.

Various refinements of the features noted above may exist in relation tovarious aspects of the present disclosure. Further features may also beincorporated in these various aspects as well. These refinements andadditional features may exist individually or in any combination. Forinstance, various features discussed below in relation to one or more ofthe illustrated embodiments may be incorporated into any of theabove-described aspects of the present disclosure alone or in anycombination. The brief summary presented above is intended only tofamiliarize the reader with certain aspects and contexts of embodimentsof the present disclosure without limitation to the claimed subjectmatter.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of this disclosure may be better understood upon readingthe following detailed description and upon reference to the drawingsdescribed below.

FIG. 1 is a block diagram of an electronic device, according to anembodiment of the present disclosure.

FIG. 2 is a perspective view of a notebook computer representing anembodiment of the electronic device of FIG. 1.

FIG. 3 is a front view of a handheld device representing anotherembodiment of the electronic device of FIG. 1.

FIG. 4 is a front view of another handheld device representing anotherembodiment of the electronic device of FIG. 1.

FIG. 5 is a front view of a desktop computer representing anotherembodiment of the electronic device of FIG. 1.

FIG. 6 is a perspective view of a wearable electronic devicerepresenting another embodiment of the electronic device of FIG. 1.

FIG. 7 is a block diagram of example transceiver circuitry of theelectronic device of FIG. 1, according to an embodiment of the presentdisclosure.

FIG. 8A is a block diagram of receiver circuitry of the exampletransceiver circuitry of FIG. 7, according to an embodiment of thepresent disclosure.

FIG. 8B is a block diagram of transmitter circuitry of the exampletransceiver circuitry of FIG. 7, according to an embodiment of thepresent disclosure.

FIG. 9 is a schematic diagram of the example transceiver circuitry ofFIG. 7, according to an embodiment of the present disclosure.

FIG. 10 is a schematic diagram of an embodiment of the transceivercircuitry of FIG. 9 having a feedback path that reduces or compensatesfor a leakage signal from the transmitter circuitry to the receivercircuitry.

FIG. 11 is a schematic diagram of an embodiment of the transceivercircuitry of FIG. 9 having a feedback path that reduces or compensatesfor a leakage signal from the transmitter circuitry to the receivercircuitry, where the leakage signal includes noise signals.

FIG. 12 is a schematic diagram of an embodiment of the transceivercircuitry of FIG. 9 having a feedback path that reduces or compensatesfor noise signals generated by the transmitter circuitry at the receivercircuitry.

FIG. 13 is a schematic diagram of an example embodiment of thetransceiver circuitry of the electronic device of FIG. 1 that reduces orcompensates for leakage and noise signals associated with a transmissionsignal at the receiver circuitry using two feedback paths according tothe embodiments of FIG. 10 and FIG. 12.

FIG. 14 is a schematic diagram of another example embodiment of thetransceiver circuitry of the electronic device of FIG. 1 that reduces orcompensates for leakage and noise signals associated with a transmissionsignal at the receiver circuitry using two feedback paths according tothe embodiments of FIG. 11 and FIG. 12.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

One or more specific embodiments will be described below. In an effortto provide a concise description of these embodiments, not all featuresof an actual implementation are described in the specification. Itshould be appreciated that in the development of any such actualimplementation, as in any engineering or design project, numerousimplementation-specific decisions must be made to achieve thedevelopers' specific goals, such as compliance with system-related andbusiness-related constraints, which may vary from one implementation toanother. Moreover, it should be appreciated that such a developmenteffort might be complex and time consuming, but would nevertheless be aroutine undertaking of design, fabrication, and manufacture for those ofordinary skill having the benefit of this disclosure.

When introducing elements of various embodiments of the presentdisclosure, the articles “a,” “an,” and “the” are intended to mean thatthere are one or more of the elements. The terms “comprising,”“including,” and “having” are intended to be inclusive and mean thatthere may be additional elements other than the listed elements.Additionally, it should be understood that references to “oneembodiment” or “an embodiment” of the present disclosure are notintended to be interpreted as excluding the existence of additionalembodiments that also incorporate the recited features. Use of the term“approximately,” “near,” “about”, and/or “substantially” should beunderstood to mean including close to a target (e.g., design, value,amount), such as within a margin of any suitable or contemplatable error(e.g., within 0.1% of a target, within 1% of a target, within 5% of atarget, within 10% of a target, within 25% of a target, and so on).

With the foregoing in mind, there are many suitable communicationdevices that may include and use transceiver circuitry that reduces orcompensates for leakage or noise signals from transmitter circuitry toreceiver circuitry, as described herein. Turning first to FIG. 1, anelectronic device 10 according to an embodiment of the presentdisclosure may include, among other things, a processor core complex 12including one or more processor(s), memory 14, nonvolatile storage 16, adisplay 18, input structures 22, an input/output (I/O) interface 24, anetwork interface 25, and a power source 30. The various functionalblocks shown in FIG. 1 may include hardware elements (includingcircuitry), software elements (including computer code stored on acomputer-readable medium) or a combination of both hardware and softwareelements. It should be noted that FIG. 1 is merely one example of aparticular implementation and is intended to illustrate the types ofcomponents that may be present in electronic device 10.

By way of example, the electronic device 10 may represent a blockdiagram of the notebook computer depicted in FIG. 2, the handheld devicedepicted in FIG. 3, the handheld device depicted in FIG. 4, the desktopcomputer depicted in FIG. 5, the wearable electronic device depicted inFIG. 6, or similar devices. It should be noted that the processor(s) 12and other related items in FIG. 1 may be generally referred to herein as“data processing circuitry.” Such data processing circuitry may beembodied wholly or in part as software, software, hardware, or anycombination thereof. Furthermore, the processor(s) 12 and other relateditems in FIG. 1 may be a single contained processing module or may beincorporated wholly or partially within any of the other elements withinthe electronic device 10.

In the electronic device 10 of FIG. 1, the processor(s) 12 may beoperably coupled with a memory 14 and a nonvolatile storage 16 toperform various algorithms. Such programs or instructions executed bythe processor(s) 12 may be stored in any suitable article of manufacturethat includes one or more tangible, computer-readable media. Thetangible, computer-readable media may include the memory 14 and/or thenonvolatile storage 16, individually or collectively, to store theinstructions or routines. The memory 14 and the nonvolatile storage 16may include any suitable articles of manufacture for storing data andexecutable instructions, such as random-access memory, read-only memory,rewritable flash memory, hard drives, and optical discs. In addition,programs (e.g., an operating system) encoded on such a computer programproduct may also include instructions that may be executed by theprocessor(s) 12 to enable the electronic device 10 to provide variousfunctionalities.

In certain embodiments, the display 18 may be a liquid crystal display(LCD), which may facilitate users to view images generated on theelectronic device 10. In some embodiments, the display 18 may include atouch screen, which may facilitate user interaction with a userinterface of the electronic device 10. Furthermore, it should beappreciated that, in some embodiments, the display 18 may include one ormore light-emitting diode (LED) displays, organic light-emitting diode(OLED) displays, active-matrix organic light-emitting diode (AMOLED)displays, or some combination of these and/or other displaytechnologies.

The input structures 22 of the electronic device 10 may enable a user tointeract with the electronic device 10 (e.g., pressing a button toincrease or decrease a volume level). The I/O interface 24 may enableelectronic device 10 to interface with various other electronic devices,as may the network interface 25. The network interface 25 may include,for example, one or more interfaces for a personal area network (PAN),such as a BLUETOOTH® network, for a local area network (LAN) or wirelesslocal area network (WLAN), such as an 802.11x WI-FI® network, and/or fora wide area network (WAN), such as a 3^(rd) generation (3G) cellularnetwork, universal mobile telecommunication system (UMTS), 4^(th)generation (4G) cellular network, long term evolution (LTE®) cellularnetwork, long term evolution license assisted access (LTE-LAA) cellularnetwork, 5^(th) generation (5G) cellular network, and/or New Radio (NR)cellular network. In particular, the network interface 25 may include,for example, one or more interfaces for using a Release-15 cellularcommunication standard of the 5G specifications that include themillimeter wave (mmWave) frequency range (e.g., 24.25-300 gigahertz(GHz)). The network interface 25 of the electronic device 10 may allowcommunication over the aforementioned networks (e.g., 5G, Wi-Fi,LTE-LAA, and so forth).

The network interface 25 may also include one or more interfaces, forexample, for broadband fixed wireless access networks (e.g., WIMAX®),mobile broadband Wireless networks (mobile WIMAX®), asynchronous digitalsubscriber lines (e.g., ADSL, VDSL), digital videobroadcasting-terrestrial (DVB-T®) network and its extension DVB Handheld(DVB-H®) network, ultra-wideband (UWB) network, alternating current (AC)power lines, and so forth. In some embodiments, network interfaces 25may be capable of joining multiple networks, and may employ one or moreantennas 20 to that end.

In some examples, the network interface 25 may include a transceivercircuitry 29, among other things. The transceiver circuitry 29 mayfacilitate communication via the one or more antennas 20 to enable theelectronic device 10 to transmit and receive wireless signals. Thetransceiver circuitry 29 may include isolation circuitry 26, a receiver27, and a transmitter 28. The isolation circuitry 26 may enablebidirectional communication over a shared signal path while separatingsignals traveling in each direction from one another. In particular, theisolation circuitry 26 may isolate the transmitter 28 from a receivedsignal and/or isolate the receiver 27 from a transmission signal (e.g.,isolate the transmitter from the receiver, and vice versa) to enablebidirectional communication.

In some embodiments, the isolation circuitry 26 may include one or moreduplexers (e.g., a double balance duplexer (DBD)) that isolates thetransmitter 28 from a received signal and/or isolates the receiver 27from a transmission signal. In different embodiments, the isolationcircuitry 26 may use different electrical components (e.g.,balance-unbalance transformers or baluns) for providing the describedisolation. However, one or more components of the isolation circuitry 26may include non-ideal electrical characteristics. Such non-idealcharacteristics of components associated with the network interface 25may disturb the duplex function and degrade isolation between thetransmitter 28 and the receiver 27. To prevent such disruption,additional circuitry may be used to reduce the effect of components withnon-ideal characteristics in the receiver 27.

In some embodiments, the network interface 25 may transmit and receiveRF signals to support voice and/or data communication in wirelessapplications such as, for example, PAN networks (e.g., BLUETOOTH®), WLANnetworks (e.g., 802.11x WI-FI®), WAN networks (e.g., 3G, 4G, 5G, NR, andLTE® and LTE-LAA cellular networks), WIMAX® networks, mobile WIMAX®networks, ADSL and VDSL networks, DVB-T® and DVB-H® networks, UWBnetworks, and so forth. As further illustrated, the electronic device 10may include the power source 30. The power source 30 of the electronicdevice 10 may include any suitable source of power, such as arechargeable lithium polymer (Li-poly) battery and/or an alternatingcurrent (AC) power converter.

In certain embodiments, the electronic device 10 may take the form of acomputer, a portable electronic device, a wearable electronic device, orother type of electronic device. Such computers may be generallyportable (such as laptop, notebook, and tablet computers), or generallyused in one place (such as conventional desktop computers, workstations,and/or servers). In certain embodiments, the electronic device 10 in theform of a computer may be a model of a MacBook®, MacBook® Pro, MacBookAir®, iMac®, Mac® mini, or Mac Pro® available from Apple Inc. ofCupertino, Calif.

By way of example, the electronic device 10, taking the form of anotebook computer 10A, is illustrated in FIG. 2 in accordance with oneembodiment of the present disclosure. The depicted notebook computer 10Amay include a housing or enclosure 36, a display 18, input structures22, and ports of an I/O interface 24. In one embodiment, the inputstructures 22 (such as a keyboard and/or touchpad) may be used tointeract with the computer 10A, such as to start, control, or operate agraphical user interface (GUI) and/or applications running on computer10A. For example, a keyboard and/or touchpad may allow a user tonavigate a user interface and/or application interface displayed ondisplay 18.

FIG. 3 depicts a front view of a handheld device 10B, which representsone embodiment of the electronic device 10. The handheld device 10B mayrepresent, for example, a portable phone, a media player, a personaldata organizer, a handheld game platform, or any combination of suchdevices. By way of example, the handheld device 10B may be a model of aniPod® or iPhone® available from Apple Inc. of Cupertino, Calif. Thehandheld device 10B may include an enclosure 36 to protect interiorcomponents from physical damage and/or to shield them fromelectromagnetic interference. The enclosure 36 may surround the display18. The I/O interfaces 24 may open through the enclosure 36 and mayinclude, for example, an I/O port for a hardwired connection forcharging and/or content manipulation using a standard connector andprotocol, such as the Lightning connector provided by Apple Inc. ofCupertino, Calif., a universal serial bus (USB), or other similarconnector and protocol.

The input structures 22, in combination with the display 18, may allow auser to control the handheld device 10B. For example, the inputstructures 22 may activate or deactivate the handheld device 10B,navigate the user interface to a home screen, a user-configurableapplication screen, and/or activate a voice-recognition feature of thehandheld device 10B. Other input structures 22 may provide volumecontrol, or may toggle between vibrate and ring modes. The inputstructures 22 may also include a microphone that may obtain a user'svoice for various voice-related features, and a speaker that may enableaudio playback and/or certain phone capabilities. The input structures22 may also include a headphone input that may provide a connection toexternal speakers and/or headphones.

FIG. 4 depicts a front view of another handheld device 10C, whichrepresents another embodiment of the electronic device 10. The handhelddevice 10C may represent, for example, a tablet computer, or one ofvarious portable computing devices. By way of example, the handhelddevice 10C may be a tablet-sized embodiment of the electronic device 10,which may be, for example, a model of an iPad® available from Apple Inc.of Cupertino, Calif.

Turning to FIG. 5, a computer 10D may represent another embodiment ofthe electronic device 10 of FIG. 1. The computer 10D may be anycomputer, such as a desktop computer, a server, or a notebook computer,but may also be a standalone media player or video gaming machine. Byway of example, the computer 10D may be an iMac®, a MacBook®, or anothersimilar device by Apple Inc. of Cupertino, Calif. It should be notedthat the computer 10D may also represent a personal computer (PC) byanother manufacturer. A similar enclosure 36 may be provided to protectand enclose internal components of the computer 10D, such as the display18. In certain embodiments, a user of the computer 10D may interact withthe computer 10D using various peripheral input structures 22, such asthe keyboard 22A or mouse 22B (e.g., input structures 22), which mayconnect to the computer 10D.

Similarly, FIG. 6 depicts a wearable electronic device 10E representinganother embodiment of the electronic device 10 of FIG. 1 that mayoperate using the techniques described herein. By way of example, thewearable electronic device 10E, which may include a wristband 43, may bean Apple Watch® by Apple Inc. of Cupertino, Calif. However, in otherembodiments, the wearable electronic device 10E may include any wearableelectronic device such as, for example, a wearable exercise monitoringdevice (e.g., pedometer, accelerometer, heart rate monitor), or otherdevice by another manufacturer. The display 18 of the wearableelectronic device 10E may include a touch screen display 18 (e.g., LCD,LED display, OLED display, active-matrix organic light emitting diode(AMOLED) display, and so forth), as well as input structures 22, whichmay allow users to interact with a user interface of the wearableelectronic device 10E.

With the foregoing in mind, FIG. 7 is a block diagram of exampletransceiver circuitry 29, according to an embodiment of the presentdisclosure. The transceiver circuitry 29 may include the isolationcircuitry 26 communicatively coupled to and/or disposed between transmit(TX) circuitry 52 and receiver (RX) circuitry 54. In some embodiments,the isolation circuitry 26 may enable FDD. That is, the isolationcircuitry 26 may allow a transmission signal (TX signal) of a firstfrequency band to pass through from the TX circuitry 52 (e.g., via atransformer effect) to the one or more antennas 20 while blockingsignals within the first frequency band from passing through to the RXcircuitry 54. Moreover, the isolation circuitry 26 may allow a receptionsignal (RX signal) of a second frequency band to pass through from theantennas 20 to the RX circuitry 54 (e.g., via circuit paths) whileblocking signals within the second frequency band from passing throughto the TX circuitry 52.

Each frequency band may be of any suitable bandwidth, such as between 1megahertz (MHz) and 100 gigahertz (GHz) (e.g., 10 MHz), and include anysuitable frequencies. For example, the first frequency band (e.g., theTX frequency band) may be between 880 and 890 MHz, and the secondfrequency band (e.g., the RX frequency band) may be between 925 and 936MHz.

A shared path 60 may couple the isolation circuitry 26 to the one ormore antennas 20. The shared path 60 may be bidirectional and may enablecommunication of the TX signal from the TX circuitry 52 to the one ormore antennas 20, and/or the RX signal from the one or more antennas 20to the RX circuitry 54.

FIG. 8A is a schematic diagram of the TX circuitry 52, according to anembodiment of the present disclosure. As illustrated, the TX circuitry52 may include, for example, a power amplifier (PA) 70, a modulator 72,and a digital-to-analog converter (DAC) 74. In some embodiments, the TXcircuitry 52 may include additional or alternative components.Nevertheless, a digital signal containing information to be transmittedvia the one or more antennas 20 may be provided to the DAC 74. The DAC74 may convert the received digital signal to an analog signal. Themodulator 72 may combine the converted analog signal with a carriersignal to generate a radio wave.

The PA 70 may receive the modulated signal from the modulator 72. The PA70 may then amplify the modulated signal to a suitable level to drivetransmission of the signal via the one or more antennas 20 (e.g., the TXsignal). In some embodiments, the PA 70 may output the amplified TXsignal with noise signals distorted over a wider or different range offrequency compared to the TX frequency band (e.g., within the RXfrequency band). In some embodiments, the PA-generated noise signals maytraverse the isolation circuitry 26 to the RX circuitry 54 and maydegrade a signal integrity of the RX signal. For example, thePA-generated noise signals may distort the RX signal within the RXcircuitry 54. In additional or alternative embodiments, the TX signalmay include noise signals (e.g., within the RX frequency band) generatedby other electrical components associated with different circuitry thatmay traverse the isolation circuitry 26 to the RX circuitry 54 and maydegrade the signal integrity of the RX signal.

FIG. 8B is a schematic diagram of the RX circuitry 54, according to anembodiment of the present disclosure. As illustrated, the RX circuitry54 may include, for example, a low noise amplifier (LNA) 80, ademodulator 82, and an analog-to-digital converter (ADC) 84. One or moresignals received by the one or more antennas 20 may be sent to the RXcircuitry 54 via the isolation circuitry 26. In some embodiments, the RXcircuitry 54 may include additional or alternative components.

The LNA 80 may receive the RX signal received by the one or moreantennas 20 via the isolation circuitry 26. Subsequently, the RX signalis sent to the demodulator 82. The demodulator 82 may remove the RFenvelope and extract a demodulated signal from the RX signal forprocessing. The ADC 84 receives the demodulated analog signal andconverts the signal to a digital signal so that it can be furtherprocessed by the electronic device 10.

In some cases, the LNA 80 may also receive other signals (e.g., noisesignals, PA-generated noise signals, etc.) through the isolationcircuitry 26. The LNA 80 may additionally or alternatively receive aleakage signal or current associated with the TX circuitry 52 sendingthe TX signal (e.g., a portion of the TX signal that leaks from the oneor more antennas 20). The LNA 80 may amplify the RX signal to a suitablelevel for the rest of the circuitry to process. However, the LNA 80 mayalso amplify the other received signals (e.g., noise signals,PA-generated noise signals, etc.). As such, the demodulator 82 mayreceive the amplified RX signal with amplified noise and/or leakagesignals, which may interfere with the RX signal and result in reducedsignal integrity. Embodiments are described below that reduce and/orcompensate for the noise and/or leakage signals generated by the TXcircuitry 52 and arriving at the RX circuitry 54 to prevent disruptionof RX signals. Specifically, a noise canceller signal and/or leakagecanceller signal may be generated at the TX circuitry 52 and providedvia one or more feedback paths to the RX circuitry 54.

With the foregoing in mind, FIG. 9 is a schematic diagram of at least aportion of example transceiver circuitry 29 associated with FIG. 7,according to an embodiment of the present disclosure. Specifically, FIG.9 depicts a TX signal 92 generated and sent from the TX circuitry 52,through a duplexer 57A of the isolation circuitry 26, to the one or moreantennas 20 for transmission. Moreover, the RX circuitry 54 may receivean RX signal 94 via the one or more antennas 20 through a duplexer 57Bof the isolation circuitry 26 to reach the RX circuitry 54 forreception. The isolation circuitry 26, including the two duplexers 57Aand 57B, may be referred to as an electrical balanced duplexer (EBD).The duplexer 57B may block the TX signal 92 from the RX circuitry 54.Moreover, the duplexer 57A may block the RX signal 94 from the TXcircuitry 52. As such, the duplexer 57A and the duplexer 57B mayfacilitate bidirectional communication of the TX signal 92 and the RXsignal 94 over a shared path 96 using FDD techniques. It should beappreciated that FIG. 9 depicts an example embodiment of the isolationcircuitry 26, and different circuitry, electrical components, and/ortechniques may be used in other embodiments to provide isolation betweenthe TX signal 92 and the RX circuitry 54 and/or the RX signal 94 and theTX circuitry 52.

The duplexer 57A may include tunable impedance components, such as atransmitter impedance gradient (TX IG) 102 and a transmitter impedancetuner (TX IT) 104, to facilitate transmission of the TX signal 92 whileproviding electrical isolation from signals outside the TX frequencyband. In specific embodiments, the TX IG 102 and the TX IT 104 mayprovide unbalanced and unmatched impedance with respect to signalswithin the TX frequency band to enable such signals to pass through. Forexample, the TX IG 102 may provide a low impedance and the TX IT 104 mayprovide a high impedance. This unbalanced impedance state may enable theTX signals (e.g., the TX signal 92) to travel from the TX circuitry 52across the first balun 98 to the shared path 96. Moreover, the TX IG 102and the TX IT 104 may provide balanced and matched impedance withrespect to signals outside the TX frequency band to prevent such signalsfrom passing through. For example, the TX IG 102 and the TX IT 104 mayboth provide a high impedance with respect to signals outside the TXfrequency band. As such, this balanced impedance state may preventsignals outside the TX frequency band (e.g., within the RX frequencyband) from traveling from the first balun 98 to the TX circuitry 52. Itshould be understood that the TX IG 102 and the TX IT 104 are providedas examples, and any suitable tunable impedance components may be used.

Similarly, the duplexer 57B may provide electrical isolation for signalsoutside the RX frequency band. That is, the duplexer 57B may enable theRX signal 94, within the RX frequency band, to pass through a secondbalun 100 from the shared path 96 (e.g., received via the one or moreantennas 20) to the RX circuitry 54 (e.g., input to the LNA 80).Moreover, the duplexer 57B may prevent signals (e.g., currents) outsidethe RX frequency band from traversing the second balun 100, thus,isolating the RX circuitry 54 from the TX signal 92 and noise signals,among other things.

In particular, the second portion of the duplexer 57B may include areceiver impedance gradient (RX IG) 106 and a receiver impedance tuner(RX IT) 108 to facilitate reception of the RX signal 94 while providingelectrical isolation against signals outside the RX frequency band. Inspecific embodiments, the RX IG 106 and the RX IT 108 may provideunbalanced and unmatched impedance with respect to signals within the RXfrequency band to enable such signals to pass through. For example, withrespect to signals within the RX frequency band, the RX IG 106 mayprovide a low impedance to a first side of the second balun 100 and theRX IT 108 may provide a high impedance to a second side of the secondbalun 100. This unbalanced impedance state may enable the RX signals(e.g., the RX signal 94) to travel from the one or more antennas 20across the second balun 100 to the RX circuitry 54. Additionally, the RXIG 106 and the RX IT 108 may provide balanced and matched impedance withrespect to signals outside the RX frequency band (e.g., within the TXfrequency band). For example, with respect to signals outside the RXfrequency band, the RX IG 106 and the RX IT 108 may both provide a highimpedance with respect to signals outside the RX frequency band. Thisbalanced impedance state may prevent signals outside the RX frequencyband from traveling from the second balun 100 to the RX circuitry 54. Itshould be understood that the RX IG 106 and the RX IT 108 are providedas examples, and any suitable tunable impedance components may be used.

However, the electrical isolation between the TX signal 92 and the RXcircuitry 54 may benefit from additional electrical isolation. Inparticular, because the isolation provided by the duplexers 57A and 57Bmay be non-ideal (e.g., limited in real-world conditions or whenimplemented) when transmitting the TX signal 92, a portion of the TXsignal (e.g., a leakage current or signal) may leak to the RX circuitry54. That is, the RX IG 106 and/or the RX IT 108 may include less thanideal electrical characteristics. Hence, the RX IG 106 and the RX IT 108may experience at least some or partially unbalanced (e.g., and/orunmatched) impedances, which may cause leakage of some electricalcurrent associated with the TX signal 92 to the RX circuitry 54.Moreover, the second portion of the duplexer 57B is susceptible to noisesignals within the RX frequency band. For example, the PA 70, whenamplifying the TX signal for transmission with sufficient electricalpower, may introduce noise signals (e.g., including in the RX frequencyrange) to the TX signal 92 that may traverse the first balun 98 and thesecond balun 100 and cause interference with the RX signal 94. To reduceor cancel the leakage and/or noise signals, a noise canceller signaland/or leakage canceller signal may be generated at the TX circuitry 52and provided via one or more feedback paths to the RX circuitry 54, asdiscussed in more detail below. This may result in additional or betterisolation for the RX circuitry 54 from the TX signal 92.

FIG. 10 is a schematic diagram of a first embodiment of the transceivercircuitry 29 of FIG. 9 including a feedback path 110 electricallycoupled to an input of the PA 70 that provides a leakage cancellersignal 112 (e.g., a feedback signal) to cancel or reduce a leakagesignal 116 of the TX signal 92. In particular, the TX circuitry 52 maygenerate and send the TX signal 92 within the TX frequency band to betransmitted using the one or more antennas 20. The PA 70 may amplify theTX signal 92 and the TX signal 92 may pass through the first balun 98and the shared signal path 96 for transmission via the antennas 20.

The second balun 100 may prevent the TX signal 92 to pass through to theRX circuitry 54 from the shared signal path 96. However, due toreal-world variations in electrical characteristics of differentelectrical components, such as the second balun 100, the RX IG 106,and/or the RX IT 108, a portion of the TX signal 92 (e.g., a leakagecurrent or signal 116) may leak from the shared signal path 96 to thesecond balun 100. If not accounted for, the leakage signal 116 may causesensitivity degradation at the RX circuitry 54 and/or interfere with anRX signal 94 received at the RX circuitry 54.

As mentioned above, the feedback path 110 may provide the leakagecanceller signal 112 to reduce or cancel the leakage signal 116. Thefeedback path 110 may be electrically coupled to an input of the PA 70at a node 114 (e.g., between the modulator 72 and the PA 70) to providethe leakage canceller signal 112. As such, the transceiver circuitry 29may include circuitry on the feedback path 110 to facilitate cancellingthe leakage signal 116

In some embodiments, the feedback path 110 may include phase adjustmentcircuitry 118 and gain adjustment circuitry 120 to facilitate cancellingthe leakage signal 116. The phase adjustment circuitry 118 may adjust aphase of the leakage canceller signal 112. For example, the feedbackpath 110 may use the phase adjustment circuitry to provide the leakagecanceller signal 112, 180 degrees out of phase compared to the TX signal92 to cancel the leakage signal 116. In some embodiments, thetransceiver circuitry 29 may include phase sensing circuitry todetermine the phase of the TX signal 92, so that the phase adjustmentcircuitry 118 may better tune the phase of the leakage canceller signal112 to be 180 degrees out of phase compared to the TX signal 92.

Moreover, the gain adjustment circuitry 120 may adjust an amplitude ofthe leakage canceller signal 112 to correlate to or match the amplitudeof the leakage signal 116 to reduce or cancel the leakage signal 116. Insome embodiments, the transceiver circuitry 29 may include gain oramplitude sensing circuitry to determine the amplitude of the leakagesignal 116, so that the gain adjustment circuitry 120 may better tunethe amplitude of the leakage canceller signal 112 to correlate to ormatch the amplitude of the leakage signal 116. As such, the feedbackpath 110 may provide the leakage canceller signal 112 to the RXcircuitry 54 to reduce or compensate for an effect of the leakage signal116 on RX signals.

FIG. 11 is a schematic diagram of a second embodiment of the transceivercircuitry 29 of FIG. 9 including a feedback path 111 electricallycoupled to an output of the PA 70. The feedback path 111 may provide theleakage canceller signal 112 (e.g., a leakage canceller signal) tocancel or reduce the leakage signal 116 from the TX signal 92. Aspreviously discussed, the PA 70 may amplify the TX signal 92 and theamplified TX signal 92 may pass through the first balun 98 and theshared signal path 96 for transmission via the one or more antennas 20.Because the feedback path 111 is coupled to the output of the PA 70, theleakage canceller signal 112 may include noise (e.g., outside of the TXfrequency band, such as within the RX frequency band) generated by thePA 70. As such, the transceiver circuitry 29 may include circuitry onthe feedback path 111 to filter such noise from the leakage cancellersignal 112, such that the leakage canceller signal 112 may bettercorrelate to and compensate for the TX signal 92.

As illustrated, the feedback path 111 includes, in addition to the phaseadjustment circuitry 118 and the gain adjustment circuitry 120, a bandpass filter (BPF) 130. The BPF 130 may enable TX frequency band signalsto pass through, and block signals outside of the TX frequency band frompassing through. As such, the BPF 130 may facilitate cancelling theleakage signal 116 at the RX circuitry 54. As with the transceivercircuitry 29 described in FIG. 10, the phase adjustment circuitry 118may adjust a phase of the leakage canceller signal 112 to correlate to(e.g., 180 degree out of phase compared to) a phase of the leakagesignal 116. Moreover, gain adjustment circuitry 120 may adjust anamplitude of the leakage canceller signal 112 to correlate to or matchthe amplitude of the leakage signal 116. As such, the feedback path 111may provide the leakage canceller signal 112 to the RX circuitry 54 toreduce an effect of the leakage signal 116. It should be understood thatbecause the transceiver circuitry 29 of FIG. 10 couples the feedbackpath 110 to an input of the PA 70 (rather than an output of the PA 70),the noise generated by the PA 70 may not be included in the leakagecanceller signal 112, and, as such, the BPF 130 may be unnecessary inthat embodiment.

FIG. 12 is a schematic diagram of a third embodiment of the transceivercircuitry 29 of FIG. 9 including a feedback path 140 electricallycoupled to an output of the PA 70 that provides a noise canceller signal142 (e.g., a feedback signal) to cancel or reduce a noise signal 143generated by the PA 70. As previously discussed, the PA 70 may amplifythe TX signal 92 with sufficient power for transmission via the antennas20. However, in operation, the PA 70 may generate a noise signal 143within the RX frequency band, which may pass through the isolationcircuitry 26 (e.g., including the first balun 98 and the second balun100) and arrive at the RX circuitry 54. For example, the noise signal143 may be a result of non-linear characteristics of the PA 70. Tocompensate for or reduce the noise signal 143, the feedback path 140 mayinclude circuitry to generate the noise canceller signal 142.

The feedback path 140 may include phase adjustment circuitry 118, gainadjustment circuitry 120, and a BPF 144. The phase adjustment circuitry118 may adjust a phase of the noise canceller signal 142 to be 180degree out of phase from the noise signal 143. In some embodiments, thetransceiver circuitry 29 may include phase sensing circuitry todetermine the phase of the noise signal 143, so that the phaseadjustment circuitry 118 may better tune the phase of the noisecanceller signal 142 to be 180 degrees out of phase compared to thenoise signal 143. Moreover, the gain adjustment circuitry 120 may adjustan amplitude of the noise canceller signal 142 to correlate to or matchthe amplitude of the noise signal 143 to reduce or cancel the noisesignal 143. In some embodiments, the transceiver circuitry 29 mayinclude gain or amplitude sensing circuitry to determine the amplitudeof the noise signal 143, so that the gain adjustment circuitry 120 maybetter tune the amplitude of the noise canceller signal 142 to correlateto or match the amplitude of the noise signal 143. As such, the feedbackpath 140 may provide the noise canceller signal 142 to the RX circuitry54 to reduce or compensate for an effect of the noise signal 143 on RXsignals.

FIG. 13 is a circuit diagram of an implementation of the second andthird embodiments of the transceiver circuitry 29 as illustrated inFIGS. 11 and 12, according to embodiments of the present disclosure. Inparticular, additional isolation circuitry 146 (e.g., in addition to theisolation circuitry 26) may be disposed on feedback paths 111, 140. Thefeedback paths 111, 140 may each electrically couple to the TX circuitry52 at the output of the PA 70 (e.g., between the output of the PA 70 andthe isolation circuitry 26) such that they may split from a node 129.

The TX IG 102 and the TX IT 104 may include unmatched impedance withrespect to signals within the TX frequency band. As such, a TX signalmay traverse the first balun 98 to the shared signal path 96 fortransmission by the one or more antennas 20. However, due to real-worlddeficiencies in the RX IG 106, the RX IT 108, and/or the second balun100, among other components, a portion of the TX signal (e.g., a leakagesignal 116) may leak to the RX circuitry 54 (instead of beingtransmitted via the one or more antennas 20). If left uncompensated, theleakage signal 116 may desense the RX circuitry 54 and/or interfere withRX signals received at the RX circuitry 54. Moreover the PA 70 of the TXcircuitry 52 may generate a noise signal 143 due to non-linearcharacteristics of the PA 70. Such noise signals may be distributedacross a wide frequency range. If left uncompensated, the noise signal143 within the RX frequency range may traverse through the first balun98 and the second balun 100 and may desense the RX circuitry 54.

As such, the feedback path 111 may provide the leakage canceller signal112 to cancel the leakage signal 116 of the TX signal and the feedbackpath 140 may provide the noise canceller signal 142 to cancel the noisesignal 143 generated by the PA 70. In particular, the feedback path 111may include the phase adjustment circuitry 118 that enables adjustingthe phase of the leakage canceller signal 112 to be 180 degrees out ofphase with respect to the leakage signal 116, the gain adjustmentcircuitry 120 that enables adjusting the amplitude of the leakagecanceller signal 112 to correlate to the amplitude of the leakage signal116, and the BPF 130 that filters out signals with frequencies outsideof the TX frequency band. In some embodiments, the BPF 130 may include abalun with respective IG and IT components to enable signals within theTX frequency band to pass through and prevent signals outside the TXfrequency band from passing through. As such, the leakage cancellersignal 112 traversing the feedback path 111 may cancel the leakagesignal 116 of the TX signal.

Moreover, the feedback path 140 may include the phase adjustmentcircuitry 118 that enables adjusting the phase of the noise cancellersignal 142 to be 180 degrees out of phase with respect to the noisesignal 143, the gain adjustment circuitry 120 that enables adjusting theamplitude of the noise canceller signal 142 to correlate to theamplitude of the noise signal 143, and the BPF 144 that filters outsignals with frequencies outside of the RX frequency band. In someembodiments, the BPF 144 may include a balun with respective IG and ITcomponents to enable signals within the RX frequency band to passthrough and prevent signals outside the RX frequency band from passingthrough. As such, the noise canceller signal 142 traversing the feedbackpath 140 may cancel the noise signal 143 generated by the PA 70.

FIG. 14 is a circuit diagram of another example of the transceivercircuitry 29 of the electronic device of FIG. 1. Additional isolationcircuitry 156 may include the first embodiment and the third embodimentof the transceiver circuitry 29, as described above, to provide theleakage canceller signal 112 and the noise canceller signal 142. Theadditional isolation circuitry 156 may use the feedback path 110 and thefeedback path 140. The feedback path 110 may couple the input of PA 70and the feedback path 140 may couple the output of the PA 70 (e.g.,before the isolation circuitry 26). It should be understood that becausethe transceiver circuitry 29 of FIG. 14 couples the feedback path 110 toan input of the PA 70, the noise generated by the PA 70 may not beincluded in the leakage canceller signal 112, and, as such, the BPF 130may be unnecessary in this embodiment.

Similar to the example of FIG. 13, the TX IG 102 and the TX IT 104 mayinclude unmatched (and unbalanced) impedance with respect to signalswithin the TX frequency band. As such, a TX signal may traverse thefirst balun 98 to the shared signal path 96 for transmission by theantennas 20. However, due to real-world deficiencies in characteristicsof the RX IG 106, the RX IT 108, the second balun 100, among otherpossibilities, the second balun 100 may leak a portion of the TX signalto the LNA 80 and the RX circuitry. The leakage signal (e.g., leakagesignal 116) may desense the RX circuitry and cause interference whenreceiving RX signals. Moreover, the PA 70 of the TX circuitry maygenerate noise signals, for example, due to non-linear characteristic ofthe PA 70. Such noise signals may dissipate across a wide frequencyrange. A portion of the noise signals that are within the RX frequencyrange may traverse through the first balun 98 and the second balun 100and may desense the RX circuitry.

As such, the feedback path 110 may provide the leakage canceller signal112 (not shown in FIG. 13) to cancel the leakage current (e.g., leakagesignal 116) of TX signal and the feedback path 140 may provide the noisecanceller signal 142 to cancel the noise signals (e.g., noise signals143) before the LNA 80 of the RX circuitry 54. In particular, thefeedback path 110 may include the phase adjustment circuitry 118 thatenables adjusting the phase of the leakage canceller signal 112 to be180 degrees out of phase with respect to the leakage signal 116, thegain adjustment circuitry 120 that enables adjusting the amplitude ofthe leakage canceller signal 112 to correlate to the amplitude of theleakage signal 116. Since feedback path 110 is electrically coupled tothe input of the PA 70, the leakage canceller signal 112 may include TXsignals within TX frequency band.

Moreover, the feedback path 140 may include the gain adjustmentcircuitry 120, the BPF 144, and the phase adjustment circuitry 118. Insome embodiments, the BPF 144 may include a balun with respective IG andIT components to provide signals within the RX frequency band from theTX circuitry to the RX circuitry. As such, the feedback path 140 maycancel the noise signals in the RX circuitry by providing the secondfeedback signal 142 using the gain adjustment circuitry 120, the BPF144, and the phase adjustment circuitry 118.

The techniques presented and claimed herein are referenced and appliedto material objects and concrete examples of a practical nature thatdemonstrably improve the present technical field and, as such, are notabstract, intangible or purely theoretical. Further, if any claimsappended to the end of this specification contain one or more elementsdesignated as “means for [perform]ing [a function] . . . ” or “step for[perform]ing [a function] . . . ,” it is intended that such elements areto be interpreted under 35 U.S.C. 112(f). However, for any claimscontaining elements designated in any other manner, it is intended thatsuch elements are not to be interpreted under 35 U.S.C. 112(f).

The invention claimed is:
 1. Radio frequency transceiver circuitrycomprising: a first balun and a second balun configured to beelectrically coupled to one or more antennas; transmit circuitryelectrically coupled to the first balun and configured to send atransmission signal via the one or more antennas; receiver circuitryelectrically coupled to the second balun and configured to receive areceive signal via the one or more antennas; and phase adjustmentcircuitry electrically coupled between the transmit circuitry and thesecond balun and configured to adjust a phase of a feedback signal, thephase adjustment circuitry configured to provide the feedback signalfrom the transmit circuitry to the second balun to compensate for aleakage or noise signal generated by the transmit circuitry when sendingthe transmission signal via the one or more antennas.
 2. The radiofrequency transceiver circuitry of claim 1, comprising gain adjustmentcircuitry configured to adjust an amplitude of the feedback signal tocompensate for the leakage or noise signal.
 3. The radio frequencytransceiver circuitry of claim 1, wherein the transmit circuitrycomprises a power amplifier having an output electrically coupled to thephase adjustment circuitry.
 4. The radio frequency transceiver circuitryof claim 3, wherein the phase adjustment circuitry is configured toadjust the phase of the feedback signal to compensate for the leakagesignal generated by the transmit circuitry when sending the transmissionsignal via the one or more antennas.
 5. The radio frequency transceivercircuitry of claim 4, wherein the power amplifier generates the noisesignal and the radio frequency transceiver circuitry comprises frequencyfiltering circuitry configured to filter the noise signal from thefeedback signal.
 6. The radio frequency transceiver circuitry of claim3, wherein the power amplifier generates the noise signal, and the phaseadjustment circuitry is configured to adjust the phase of the feedbacksignal to compensate for the noise signal generated by the poweramplifier.
 7. The radio frequency transceiver circuitry of claim 6,wherein the power amplifier generates the noise signal, and the radiofrequency transceiver circuitry comprises frequency filtering circuitryconfigured to filter signals in a frequency range associated with thetransmission signal from the feedback signal.
 8. The radio frequencytransceiver circuitry of claim 1, wherein the transmit circuitrycomprises a power amplifier having an input electrically coupled to thephase adjustment circuitry.
 9. The radio frequency transceiver circuitryof claim 8, wherein the phase adjustment circuitry is configured toadjust the phase of the feedback signal to compensate for the leakagesignal generated by the transmit circuitry when sending the transmissionsignal via the one or more antennas.
 10. An electronic devicecomprising: one or more antennas; transmission circuitry configured tosend a transmission signal to the one or more antennas; receivercircuitry configured to receive a reception signal from the one or moreantennas; isolation circuitry configured to provide electrical isolationbetween the transmission signal and the receiver circuitry, andconfigured to provide electrical isolation between the reception signaland the transmission circuitry; a feedback path between the transmissioncircuitry and the receiver circuitry configured to provide a feedbacksignal from the transmission circuitry to the receiver circuitry; andphase adjustment circuitry disposed on the feedback path and configuredto adjust a phase of the feedback signal to compensate for a leakage ornoise signal generated by the transmission circuitry when sending thetransmission signal to the one or more antennas.
 11. The electronicdevice of claim 10, comprising a shared conductive path between the oneor more antennas, the transmission circuitry, and the receivercircuitry, wherein the isolation circuitry comprises a first baluncoupled between the transmission circuitry and the shared conductivepath and a second balun coupled between the receiver circuitry and theshared conductive path.
 12. The electronic device of claim 11, whereinthe isolation circuitry comprises a first variable impedance device anda second variable impedance device coupled to the second balun, thefirst variable impedance device and the second variable impedance deviceconfigured to be in a balanced state with respect to a frequency rangeassociated with the transmission signal.
 13. The electronic device ofclaim 12, wherein the leakage signal comprises a portion of thetransmission signal generated by the transmission circuitry when sendingthe transmission signal to the one or more antennas that travels fromthe transmission circuitry, through the first balun, and to the secondbalun.
 14. The electronic device of claim 10, wherein the phaseadjustment circuitry is configured to adjust the phase of the feedbacksignal to compensate for the leakage signal, and the electronic devicecomprises a band pass filter disposed on the feedback path andconfigured to filter the noise signal from the feedback signal.
 15. Theelectronic device of claim 10, wherein the phase adjustment circuitry isconfigured to adjust the phase of the feedback signal to compensate forthe noise signal, and the electronic device comprises a band pass filterdisposed on the feedback path and configured to filter signals outside afrequency range associated with the reception signal from the feedbacksignal.
 16. The electronic device of claim 10, comprising a balundisposed on the feedback path for filtering signals outside a frequencyrange associated with the transmission signal or the reception signalfrom the feedback signal.
 17. An electronic device, comprising: antennameans; means for transmitting a transmission signal via the antennameans; means for receiving a receive signal via the antenna means; meansfor isolating the receiving means from the transmission signal, theisolating means comprising means for providing a feedback signal fromthe transmitting means to the receiving means, wherein the isolatingmeans comprise means for adjusting a phase of the feedback signal tocompensate for a leakage or noise signal generated by the transmittingmeans when transmitting the transmission signal via the antenna means.18. The electronic device of claim 17, wherein the phase adjustmentmeans is configured to adjust the phase of the feedback signal to be 180degrees out of phase with the leakage or noise signal.
 19. Theelectronic device of claim 17, wherein the isolating means furthercomprises means for adjusting an amplitude of the feedback signal tocorrelate to an amplitude of the leakage or noise signal.
 20. Theelectronic device of claim 17, wherein the isolating means furthercomprises means for filtering signals outside a frequency range from thefeedback signal.